Apparatus for projecting diapositives



May 10, 1932. H. WIRTSCHAFTER PPARATUS FOR PHOJEGTING DIPOSIIIVES Filed'Jan. 14, 1927 Patentes. May 10, 1932 UNITED STATES PATENT OFFICE HUGO WIRTSGHAIETEB, OF VIENNA, AUSTRIA A?PARATUS PROJ'EGTING DIAPOSITIVES Application fi1ed January 14, 1927, Serial N0. 161,204, nd in Austria 'J'annary 20, 1926.

It has heretofore been customary in projcting diapositives intermittcntly that tl1e diupositive in projectiou npparatus \\:flS quickly' removecl and thc next diapogitpw:

5 quickly inserted in Order t make tl1e per1od of interruption between two pic'cures on the screen as sho1't as possible. The diapositives are usually changed by band although me- 'chanical means have also become known WlIGIPlW the diapositives are stopped in the projecting machine and lhen changed intermittently. These meuns, howcver, are bulky and complicated.

In contradistinction to the above present- .ing mcthod. the method accorcling t0 the invefition is adapted especiall v f01 Text diapositives accor ling to which tho diapositives am passed by the window in a constant motion preferably automatically wlmreby the on- 100ke1 receives the illusion that a moving text film is presented, as is usual where the texts am of great. length. Moreove1, the i n terruptions occurring with the known meth- 0d for presenting diapositives and especial- 35 ly in connection with long texts are obviated. Et will also be pnssible f0r the onlooker (0 read the 1ines of the text and even texts of greater length repeatedlyund with ease, whereas it has heretofore been necessary to 50 reacl hurriedly. because 0ne did not knnw whother tl1e dlapositive vmn1cl be changed before the last lines llfl(l bcen read. Finally, special attention is called t0 the advantagre of the constant movement of the diapositive. which is not effe te d by lmnd 01 by a mot0r buttaltes place. autonxaticalh by ehe znove;

mentof tl1e diapositives through their 0wn weight.

' A modificaticn 0'f l1e method according t0 thf. i1.venon wharein a clmin of diapositives are formecl a diapositive constituting auch link consis'ts in keeping constant the cliflerence. in height 01 level between the places where the cnain links (diapositives) are de posited in Order tlmt i1he weight of the sinla ing piece of clmin ronmins unchanged.

The accompm1ying clrizwings sl1ow two modifications br' means f01 Carrying ut tl1e 0 method in which:

Fiy. l is a side view of a device fo1 carrying out the invention.

Fig. 2 shows a ser'1es o:f diapositives urticulated 130 auch other.

Figr. 3 is.a modified form 0f the invention; nn l Fig. l slmws the form of diawsitives in use with the device of Fig. 8.

Tim vonstruction acvording Figs. 1 and 2, which is very simple inaleed, comprises a clinin m: frame 1 for recei\lng tl1e cliapositives which nre flexibly connected together. The clmin is tzlken from 0110 supply rcceptncle 4 by a drun1 3 und movgd past tllf} window 2 of the projection appu rn.tus to a depositing receptacle 4: the ehgagvment between Llrum und chain is efi'ected, i'or instance, by means 0f projoctions 6 and Tecesses 10.

Tho Jillkrrencc in l1eight er level betwcen the point removal and tl1e poim'; of deposit is kept consiaut nccording t0 the inventiou, thus tl1e length and wcight respectlvely of the sinking und rising pieces nf clmin remain unchanged, which is advantageous f0r the uniform regulation 0f the speed of movement 0f tl1e device.

This is done b'y making the. receptacles 4 und -i similzu, euch having a momble member supported 011 a spring 5. In this C011- struction as weightis reliewed in one receptacle ancl weigxht is addecl in tl1e otl1er the spring in eacl1 receptacle Will move up und. down rospectivcly and proportionally.

In nrder to Control the. speed ab which Ehe. cl1a'm 1 moves, a gear wheel 8a is provicled (m tl1e slmft 0f t-l1e drum and meshes with a gear wheel 8b car'rying a flying vane .9.

The constant movement of the diapositives, tl1us provided f01' is temporarily interrupted t0 ermble indlsid1ml pictures of a series of pictures t0 be viewed along while. F01 this purpose. tl1o. drum 3, driven b v the falling clxa'm, revolves und bruslmes directly or with ifs projcc'tions 6 a gainst a stationary escapement m arr0s'ting Wheel 7 whereby the drum 3 is stopped and when driven by the chain, it turns tl1o wheel 7 so that the projection 6 is rcleased und the drum gradually revolves ag-ain with its fullperipheral velocity. This procedure is repeated during the next brush- 1 may be governed by a flying vane 9secured to transmi ssion wheels 8, the wings of the flying vane boing adjustable. The falling speed is thereby kept uniform 01 constant While the picture 'is framed and if 'necessary the speed can be varied by such adjustment.

The contrivance according (30 Figs. 3 and 4 shows several successive diapositives superposed 011 0ne connnon carrier or support 11 (such as a ha-me 0r glass plate) formed of strips and moved past the window of the projeting apparatus.

F01 presenting texts 0f greater length, a nuxnber of such slrips 11 may be used in one and the saxne projecting apparatus, wh'rch is provided above and below the window with s lides 12 and 12 respectively f0r the diapositives. Between the slides is provided as a conveyor two chains 14 bn opposite sides of the window adapted to move over upper and lower drums 20 and 20a. Each slide is formed 0f two rails 011 which the strips 11 having shoes 13 are supported. The strips are provided with projections 15 f01' engaging with the chains.

. secured t0 the top part of the sugport 11.

VVhen the strips are to be p1ace on the ra i1s 12', they are released from engagement W1th the chains.

Acc0rding 130 the invention, the re is provided at the end of the feed t1ack 12 a respring 01 the like and extending into the path 0f the descending strip in such a manner that it is turned by the lattcr in time to permit the next strip to descend into engagement. with the carr1er chains. The 1ever 16 is also Euch of these strips isprov ided with an abut-ment, Whichl, duringp v the temporary tur ning movement thereof and the release of a strip, engages before the next stri'p und thus retams the same.

The drun120 is connected by gears 8a and I the diapositives 110 vertically movable.endlass chain, wit-h means 130 bri' the.diqpositives Ieaving the end of the trau into ment with the chain thuS moving t by their weight.

2. An apparatus as claimed in Cla.iih in which several suocessive diapositives are superposed on one common carriie'g, all Carriers being arrangcd on the inclined"'track.

3. In an apparatus for projecing diaposi tives the combinacion with a projecting apparatus 0f an inclined track located ab0ve said apparatus adapted tg receive a, plurality of framed diaposit1ves, an in'clined trank 10- cated below said projecting apparatus and adapted to receive said diapositives after passing through the projecting apparatus, and conveying means for the diapositives from the upper track through the projecting apparatus t0 be received by the lower track, said conveying means including endless carriers adapted to receive und hold a diapositive from the upper track and to convey satid diapositive through the p-rojecting apparatus by the weight of the diapositives.

4. Apparatus for projecting diapositives, in combination, means to continuously move the diaposi tives through the apparatus, and means to temporarily retard the movement 0f the diapositives when the latter cover the;

window 0f the projecting apparatus.

In witness whereof I have hereunto signed my name.

HUGO WIRTSCHAFTER.

86 with a flying vane 9a, the same as the arrangement shown in Fig. 1 for controlling the speed of movernent of the chain incident to the operation of the apparatus.

W11at I claim is:

l. An apparatus for projecting diapositives in combination with an inclined track located abwe the window and adaptedio lead 

